Water circuit steam generator



' Oct. 10, 1944.

Fild Feb. 29, 1944 2 Sheets-Sheet l INVENTOR ATTORNEY- Oct. 10, 1944.NAGE. 2,360,260

WATER CIRCUIT STEAM GENERATOR Filed Feb. 29, 1944 2 Sheets-Sheet PINVENTOR ATTO R N EY Patented Get. 10, 1944 UNITED STATES:

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TENT OFFlCE 7 Claims.

My invention relates to an improvement in railroad locomotive type steamgenerators, and has for one of its objects to provide a generator ofthis general type, which is of such construction as to enable workingsteam pressures to be increased to approximately 500 p. s. i. to improvethe thermal efliciencies of conventional steam locomotives, whichusually operate at working steam pressures of around only 250 D.s.i.

It is impracticable as well as hazardous to generate steam pressuressubstantially higher than 250 p. s. i. in the conventional horizontalfire-tube, barrel type locomotive boiler. Accordingly in order that Imay go to the higher pressures above referred to, the present inventionprovides for generating the higher steam pressures in a water tubecircuit steam generator which is of such construction as to meet thespace limitations and requirements of railroad service, and produce thedesired improved-thermal efiiciency, while practically eliminating the,explosion hazards of the conventional fire-tube,

barrel type boiler.

In the accompanying drawings:

Fig. 1 is a longitudinal part sectional elevational view of oneembodiment of my invention;

Fig. 2 is a section taken on the line 22 of Fig. 1; and

Fig. 3 is a view taken on the line 33 of Fig. 1.

Referring to the drawings in detail: My improved locomotive type steamgenerator comprises an upper horizontal drum 2 providing a steam-waterseparating chamber 4. The lower water section of the drum 2 is connectedby a bank of convective heat water tubes 6 to one or more horizontalwater drums 8 located below and substantially parallel to the drum 2.

The suction side of a water pump is connected to the water drum or drums8 and the delivery side of this pump is connected to a lowerhorizontally inclined water drum l2.

M designates a by-pass for by-passing the pump I 0, which may becontrolled by suitable valve I6.

The water drum l2 constitutes the water feed of the circuit to a waterwall combustion chamber, As will appear from the drawings thiscombustion chamber comprises an upper horizontal water drum l8,communicating at one end as indicated at 20 with the steam-waterseparating chamber 4. The drum [8 preferably is below the water level inthe drum 2 and constitutes the ceiling rafter for the water wallcombustion chamber. The upper drum l8 and lower drum 12 areinterconnected by a bank of radiant heat water tubes 22 forming thewater wall sides of the combustion chamber.

Solid fuel can be burned in this combustion chamber on grates in theconventional manner or fluid fuel such as pulverized coal or oil can beinjected through a burner or burners shown diagrammatically at 24. I

In the operation of my improved steam generator, water from thesteam-water separating drum 2 flows downward through the bank ofconvective heat tubes 6 and through the lower horizontal drum or drums8. In starting up the bypass valve IB is preferably left open, so thatthe water from the drum or drums 8 by-passes the pump l0 and flows tothe drum l2 and upwardly through the radiant heat tubes 22 to the upperhorizontal drum l8, from which it passes by Way of passage 20 to thesteam-water separating drum 2. After operation has been initiated, thepump I0 is set in operation and the by-pass valve [6 closed.

The entire steam generator water circuit, except for the pump Ill andby-pass I4, is enclosed in heat insulated jacket 26.

The feed Water connection is shown at 28, while the steam circuit isfrom the steam section of the steam-water separating drum 2 throughsuperheater coil 30 to steam outlet 32 of the generator.

It will be appreciated that the water circuit steam generator abovedescribed provides a steam generator which will meet the spacelimitations and requirements of railroad service. It will beappreciated, further, that the thermal efliciency of my generator isvery much improved as compared with the conventional horizontalfire-tube, barrel type locomotive boiler, and adapted, without explosionhazards, to generate steam pressures of the order of 500 p. s. i. ascompared with the pressures around 250 p. s. i, at which theconventional locomotive boiler is operated.

It is to be understood that changes may be made in the constructionabove described 'without departing from the spirit and scope of myinvention.

What I claim is:

1. A water circuit steam generator of the locomotive type, saidgenerator comprising in combination a steam-water separating drum, alower water drum, a bank of convective heat water tubes connecting saiddrums, a water wall combustion a bank of radiant heat water tubes, saidlast mentioned water drum being in communication with said lower waterdrum thereby to provide a circuit from the'water drum below theconvective heat water tubes to the drum below the radiant heat watertubes, through said radiant heat water tubes to the drum at the upperend of the radiant heat tubes, and from thence to the steam-Waterseparating chamber, and a pump having its suction side connected to saidlower water drum and its discharge side connected to said second waterdrum.

I 2. A water circuit steam generator of the locomotive type, saidgenerator comprising in combination a steam-water separating drum, alower water drum, a bank of convective heat water tubes connecting saiddrums, a water Wall combustion chamber comprising an upper drumcommunicate ing with said steam-water separating drum and below thewater level therein, a water drum below said upper drum and connectedthereto by a bank of radiant heat water tubes, said last mentioned waterdrum being in communication with said lower water drum thereby toprovide a circuit from the water drum below the convective heat watertubes to the drum below the radiant heat jwater. tubes, through saidradiant heat water tubes to the drum at the upper end of the radiantheat tubes, and from thence to the steam-water separating chamber.

3. A water circuit steam generator of the locomotive type, saidgenerator comprising in combination a steam-water separating drum, awater drum below the same, convective heat water tubes connecting thedrums, a water wall combustion chamber comprising an upperdrumcommunicating with the steam-water separating drum, a'second water drumbelow the level of thefirst mentioned water drum and in communicationtherewith, radiant heat water tubes connecting said upper drum and thesaid second water drum to provide Water walls for the combustionchamber, whereby a circuit is provided from the steamwater separatingdrum, through the convective heat water tubes to the first mentionedwater.

drum, thence to the second mentioned water drum, and through the radiantheat water tubes to said upper drum and from the latter to thesteam-Water separating drum, a pump havingits suction side connected tothe first mentioned water drum and its discharge sideconnected to saidsecond water drum, and a valve-controlled by-pass for said pump.

4. A water circuit steam generator of the locomotive type,said-generator comprising in combination a steam-Water separating drum,a water drum below the same, convective heat water-tubes connecting thedrums, a water wall combustion chamber comprising an upper drumcommunicaing with the steam-Water separating drum and positioned belowthe water level therein, a second water drum below the level of thefirst mentioned Water drum and in communication therewith,

radiant heat water tubes'connecting said upper drum and the said secondWater drum to provide water walls for the combustion chamber, whereby acircuit is provided from the steam-water separating drum, through theconvective heat Water tubes to the first mentioned water drum, thence tothe second mentioned water drum, and through the radiant heat watertubes to said upper drum and from the latter to the steam-waterseparating drum.

5. A Water circuit steam generator of the locomotive type, saidgenerator comprising in combination a steam-water separating drum, awater drum below the same, convective heat water tubes connecting thedrums, a water wall combustion chamber comprising an upper drumcommunicating with the steam-water separating drum, a second waterdrumbelow the level of the first mentioned water drum, radiant heat watertubes connecting said upper drum and the said second water drum toprovide water walls for the combustion chamber, a pump having itssuction side connected to the water drum below the bank of Convectiveheat water tubes, and its discharge side to the Water drum below thebank of said radiant heat water tubes, to provide a circuit from thesteam-water separating chamber through said bank of convective heatwater tubes and said first mentioned Water drum, through said pump tothe second mentioned water drum, through the radiant heat water tubes tothe drum at the top vof the combustion chamber and from thence to thesteam-water separating drum.

6. A water circuit steam generator of the locomotive type, saidgenerator comprising in combination a steam-water separating drum, awater drum below the same, convective heat water tubes connecting saiddrums, a water wall combustion chamber comprising an upper .drumcommunicating with said steam-water separating drum, a second water drumbelow'the level of the first mentioned water drum, radiant heat watertubes connecting said upper drum and the said second water drum, and apump and a by-pass for the pump connecting the first'and secondmentioned water drums, thereby to establish a circuit from thesteam-water separating drum through the convective heat water tubes andradiant heat water tubes back to the steam-Water separating drum.

7. A water circuit steam generator of the locomotive type, saidgenerator comprising in com bination a steam-water separating drum, awater drum below the same, convective heat Water tubes connecting saiddrums, a Water wall combustion chamber comprising an upper drumcommunicating with said steam-water separating drum and below the levelof the water therein, a second water drum below the level of the firstmentioned water drum, radiant heat water tubes connecting said upperdrum and the said second Water drum, and a pump and a by-pass for thepump connecting the first and second mentioned water drums, thereby toestablish a circuit from the steamwater separating drum through theconvective heat water tubes and radiant heat water tubes back to thesteam-water separating drum.

THEODORE NAGEL.

